text: The Laplace number (La), also known as the Suratman number (Su), is a dimensionless number used in the characterization of free surface fluid dynamics.  It represents a ratio of surface tension to the momentum-transport (especially dissipation) inside a fluid.
  It is defined as follows:
  where:
  * σ = surface tension
  * ρ = density
  * L = length
  * μ = liquid viscosity
  Laplace number is related to Reynolds number (Re) and Weber number (We) in the following way: